helper/log.c

Go to the documentation of this file.

/***************************************************************************
 *   Copyright (C) 2005 by Dominic Rath                                    *
 *   Dominic.Rath@gmx.de                                                   *
 *                                                                         *
 *   Copyright (C) 2007-2010 Øyvind Harboe                                 *
 *   oyvind.harboe@zylin.com                                               *
 *                                                                         *
 *   Copyright (C) 2008 by Spencer Oliver                                  *
 *   spen@spen-soft.co.uk                                                  *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 *   This program is distributed in the hope that it will be useful,       *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
 *   GNU General Public License for more details.                          *
 *                                                                         *
 *   You should have received a copy of the GNU General Public License     *
 *   along with this program.  If not, see <http://www.gnu.org/licenses/>. *
 ***************************************************************************/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "log.h"
#include "command.h"
#include "time_support.h"

#include <stdarg.h>

#ifdef _DEBUG_FREE_SPACE_
#ifdef HAVE_MALLOC_H
#include <malloc.h>
#else
#error "malloc.h is required to use --enable-malloc-logging"
#endif
#endif

int debug_level = LOG_LVL_INFO;

static FILE *log_output;
static struct log_callback *log_callbacks;

static int64_t last_time;
static int64_t current_time;

static int64_t start;

static const char * const log_strings[6] = {
    "User : ",
    "Error: ",
    "Warn : ",  /* want a space after each colon, all same width, colons aligned */
    "Info : ",
    "Debug: ",
    "Debug: "
};

static int count;

/* forward the log to the listeners */
static void log_forward(const char *file, unsigned line, const char *function, const char *string)
{
    struct log_callback *cb, *next;
    cb = log_callbacks;
    /* DANGER!!!! the log callback can remove itself!!!! */
    while (cb) {
        next = cb->next;
        cb->fn(cb->priv, file, line, function, string);
        cb = next;
    }
}

/* The log_puts() serves two somewhat different goals:
 *
 * - logging
 * - feeding low-level info to the user in GDB or Telnet
 *
 * The latter dictates that strings without newline are not logged, lest there
 * will be *MANY log lines when sending one char at the time(e.g.
 * target_request.c).
 *
 */
static void log_puts(enum log_levels level,
    const char *file,
    int line,
    const char *function,
    const char *string)
{
    char *f;

    if (!log_output) {
        /* log_init() not called yet; print on stderr */
        fputs(string, stderr);
        fflush(stderr);
        return;
    }

    if (level == LOG_LVL_OUTPUT) {
        /* do not prepend any headers, just print out what we were given and return */
        fputs(string, log_output);
        fflush(log_output);
        return;
    }

    f = strrchr(file, '/');
    if (f != NULL)
        file = f + 1;

    if (strlen(string) > 0) {
        if (debug_level >= LOG_LVL_DEBUG) {
            /* print with count and time information */
            int64_t t = timeval_ms() - start;
#ifdef _DEBUG_FREE_SPACE_
            struct mallinfo info;
            info = mallinfo();
#endif
            fprintf(log_output, "%s%d %" PRId64 " %s:%d %s()"
#ifdef _DEBUG_FREE_SPACE_
                " %d"
#endif
                ": %s", log_strings[level + 1], count, t, file, line, function,
#ifdef _DEBUG_FREE_SPACE_
                info.fordblks,
#endif
                string);
        } else {
            /* if we are using gdb through pipes then we do not want any output
             * to the pipe otherwise we get repeated strings */
            fprintf(log_output, "%s%s",
                (level > LOG_LVL_USER) ? log_strings[level + 1] : "", string);
        }
    } else {
        /* Empty strings are sent to log callbacks to keep e.g. gdbserver alive, here we do
         *nothing. */
    }

    fflush(log_output);

    /* Never forward LOG_LVL_DEBUG, too verbose and they can be found in the log if need be */
    if (level <= LOG_LVL_INFO)
        log_forward(file, line, function, string);
}

void log_printf(enum log_levels level,
    const char *file,
    unsigned line,
    const char *function,
    const char *format,
    ...)
{
    char *string;
    va_list ap;

    count++;
    if (level > debug_level)
        return;

    va_start(ap, format);

    string = alloc_vprintf(format, ap);
    if (string != NULL) {
        log_puts(level, file, line, function, string);
        free(string);
    }

    va_end(ap);
}

void log_vprintf_lf(enum log_levels level, const char *file, unsigned line,
        const char *function, const char *format, va_list args)
{
    char *tmp;

    count++;

    if (level > debug_level)
        return;

    tmp = alloc_vprintf(format, args);

    if (!tmp)
        return;

    /*
     * Note: alloc_vprintf() guarantees that the buffer is at least one
     * character longer.
     */
    strcat(tmp, "\n");
    log_puts(level, file, line, function, tmp);
    free(tmp);
}

void log_printf_lf(enum log_levels level,
    const char *file,
    unsigned line,
    const char *function,
    const char *format,
    ...)
{
    va_list ap;

    va_start(ap, format);
    log_vprintf_lf(level, file, line, function, format, ap);
    va_end(ap);
}

COMMAND_HANDLER(handle_debug_level_command)
{
    if (CMD_ARGC == 1) {
        int new_level;
        COMMAND_PARSE_NUMBER(int, CMD_ARGV[0], new_level);
        if ((new_level > LOG_LVL_DEBUG_IO) || (new_level < LOG_LVL_SILENT)) {
            LOG_ERROR("level must be between %d and %d", LOG_LVL_SILENT, LOG_LVL_DEBUG_IO);
            return ERROR_COMMAND_SYNTAX_ERROR;
        }
        debug_level = new_level;
    } else if (CMD_ARGC > 1)
        return ERROR_COMMAND_SYNTAX_ERROR;

    command_print(CMD, "debug_level: %i", debug_level);

    return ERROR_OK;
}

COMMAND_HANDLER(handle_log_output_command)
{
    if (CMD_ARGC == 0 || (CMD_ARGC == 1 && strcmp(CMD_ARGV[0], "default") == 0)) {
        if (log_output != stderr && log_output != NULL) {
            /* Close previous log file, if it was open and wasn't stderr. */
            fclose(log_output);
        }
        log_output = stderr;
        LOG_DEBUG("set log_output to default");
        return ERROR_OK;
    }
    if (CMD_ARGC == 1) {
        FILE *file = fopen(CMD_ARGV[0], "w");
        if (file == NULL) {
            LOG_ERROR("failed to open output log '%s'", CMD_ARGV[0]);
            return ERROR_FAIL;
        }
        if (log_output != stderr && log_output != NULL) {
            /* Close previous log file, if it was open and wasn't stderr. */
            fclose(log_output);
        }
        log_output = file;
        LOG_DEBUG("set log_output to \"%s\"", CMD_ARGV[0]);
        return ERROR_OK;
    }

    return ERROR_COMMAND_SYNTAX_ERROR;
}

static const struct command_registration log_command_handlers[] = {
    {
        .name = "log_output",
        .handler = handle_log_output_command,
        .mode = COMMAND_ANY,
        .help = "redirect logging to a file (default: stderr)",
        .usage = "[file_name | \"default\"]",
    },
    {
        .name = "debug_level",
        .handler = handle_debug_level_command,
        .mode = COMMAND_ANY,
        .help = "Sets the verbosity level of debugging output. "
            "0 shows errors only; 1 adds warnings; "
            "2 (default) adds other info; 3 adds debugging; "
            "4 adds extra verbose debugging.",
        .usage = "number",
    },
    COMMAND_REGISTRATION_DONE
};

int log_register_commands(struct command_context *cmd_ctx)
{
    return register_commands(cmd_ctx, NULL, log_command_handlers);
}

void log_init(void)
{
    /* set defaults for daemon configuration,
     * if not set by cmdline or cfgfile */
    char *debug_env = getenv("OPENOCD_DEBUG_LEVEL");
    if (NULL != debug_env) {
        int value;
        int retval = parse_int(debug_env, &value);
        if (ERROR_OK == retval &&
                debug_level >= LOG_LVL_SILENT &&
                debug_level <= LOG_LVL_DEBUG_IO)
                debug_level = value;
    }

    if (log_output == NULL)
        log_output = stderr;

    start = last_time = timeval_ms();
}

int set_log_output(struct command_context *cmd_ctx, FILE *output)
{
    log_output = output;
    return ERROR_OK;
}

/* add/remove log callback handler */
int log_add_callback(log_callback_fn fn, void *priv)
{
    struct log_callback *cb;

    /* prevent the same callback to be registered more than once, just for sure */
    for (cb = log_callbacks; cb; cb = cb->next) {
        if (cb->fn == fn && cb->priv == priv)
            return ERROR_COMMAND_SYNTAX_ERROR;
    }

    /* alloc memory, it is safe just to return in case of an error, no need for the caller to
     *check this */
    cb = malloc(sizeof(struct log_callback));
    if (cb == NULL)
        return ERROR_BUF_TOO_SMALL;

    /* add item to the beginning of the linked list */
    cb->fn = fn;
    cb->priv = priv;
    cb->next = log_callbacks;
    log_callbacks = cb;

    return ERROR_OK;
}

int log_remove_callback(log_callback_fn fn, void *priv)
{
    struct log_callback *cb, **p;

    for (p = &log_callbacks; (cb = *p); p = &(*p)->next) {
        if (cb->fn == fn && cb->priv == priv) {
            *p = cb->next;
            free(cb);
            return ERROR_OK;
        }
    }

    /* no such item */
    return ERROR_COMMAND_SYNTAX_ERROR;
}

/* return allocated string w/printf() result */
char *alloc_vprintf(const char *fmt, va_list ap)
{
    va_list ap_copy;
    int len;
    char *string;

    /* determine the length of the buffer needed */
    va_copy(ap_copy, ap);
    len = vsnprintf(NULL, 0, fmt, ap_copy);
    va_end(ap_copy);

    /* allocate and make room for terminating zero. */
    /* FIXME: The old version always allocated at least one byte extra and
     * other code depend on that. They should be probably be fixed, but for
     * now reserve the extra byte. */
    string = malloc(len + 2);
    if (string == NULL)
        return NULL;

    /* do the real work */
    vsnprintf(string, len + 1, fmt, ap);

    return string;
}

char *alloc_printf(const char *format, ...)
{
    char *string;
    va_list ap;
    va_start(ap, format);
    string = alloc_vprintf(format, ap);
    va_end(ap);
    return string;
}

/* Code must return to the server loop before 1000ms has returned or invoke
 * this function.
 *
 * The GDB connection will time out if it spends >2000ms and you'll get nasty
 * error messages from GDB:
 *
 * Ignoring packet error, continuing...
 * Reply contains invalid hex digit 116
 *
 * While it is possible use "set remotetimeout" to more than the default 2000ms
 * in GDB, OpenOCD guarantees that it sends keep-alive packages on the
 * GDB protocol and it is a bug in OpenOCD not to either return to the server
 * loop or invoke keep_alive() every 1000ms.
 *
 * This function will send a keep alive packet if >500ms has passed since last time
 * it was invoked.
 *
 * Note that this function can be invoked often, so it needs to be relatively
 * fast when invoked more often than every 500ms.
 *
 */
#define KEEP_ALIVE_KICK_TIME_MS  500
#define KEEP_ALIVE_TIMEOUT_MS   1000

static void gdb_timeout_warning(int64_t delta_time)
{
    extern int gdb_actual_connections;

    if (gdb_actual_connections)
        LOG_WARNING("keep_alive() was not invoked in the "
            "%d ms timelimit. GDB alive packet not "
            "sent! (%" PRId64 " ms). Workaround: increase "
            "\"set remotetimeout\" in GDB",
            KEEP_ALIVE_TIMEOUT_MS,
            delta_time);
    else
        LOG_DEBUG("keep_alive() was not invoked in the "
            "%d ms timelimit (%" PRId64 " ms). This may cause "
            "trouble with GDB connections.",
            KEEP_ALIVE_TIMEOUT_MS,
            delta_time);
}

void keep_alive(void)
{
    current_time = timeval_ms();

    int64_t delta_time = current_time - last_time;

    if (delta_time > KEEP_ALIVE_TIMEOUT_MS) {
        last_time = current_time;

        gdb_timeout_warning(delta_time);
    }

    if (delta_time > KEEP_ALIVE_KICK_TIME_MS) {
        last_time = current_time;

        /* this will keep the GDB connection alive */
        LOG_USER_N("%s", "");

        /* DANGER!!!! do not add code to invoke e.g. target event processing,
         * jim timer processing, etc. it can cause infinite recursion +
         * jim event callbacks need to happen at a well defined time,
         * not anywhere keep_alive() is invoked.
         *
         * These functions should be invoked at a well defined spot in server.c
         */
    }
}

/* reset keep alive timer without sending message */
void kept_alive(void)
{
    current_time = timeval_ms();

    int64_t delta_time = current_time - last_time;

    last_time = current_time;

    if (delta_time > KEEP_ALIVE_TIMEOUT_MS)
        gdb_timeout_warning(delta_time);
}

/* if we sleep for extended periods of time, we must invoke keep_alive() intermittently */
void alive_sleep(uint64_t ms)
{
    uint64_t napTime = 10;
    for (uint64_t i = 0; i < ms; i += napTime) {
        uint64_t sleep_a_bit = ms - i;
        if (sleep_a_bit > napTime)
            sleep_a_bit = napTime;

        usleep(sleep_a_bit * 1000);
        keep_alive();
    }
}

void busy_sleep(uint64_t ms)
{
    uint64_t then = timeval_ms();
    while (timeval_ms() - then < ms) {
        /*
         * busy wait
         */
    }
}

/* Maximum size of socket error message retrieved from operation system */
#define MAX_SOCKET_ERR_MSG_LENGTH 256

/* Provide log message for the last socket error.
   Uses errno on *nix and WSAGetLastError() on Windows */
void log_socket_error(const char *socket_desc)
{
    int error_code;
#ifdef _WIN32
    error_code = WSAGetLastError();
    char error_message[MAX_SOCKET_ERR_MSG_LENGTH];
    error_message[0] = '\0';
    DWORD retval = FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, error_code, 0,
        error_message, MAX_SOCKET_ERR_MSG_LENGTH, NULL);
    error_message[MAX_SOCKET_ERR_MSG_LENGTH - 1] = '\0';
    const bool have_message = (retval != 0) && (error_message[0] != '\0');
    LOG_ERROR("Error on socket '%s': WSAGetLastError==%d%s%s.", socket_desc, error_code,
        (have_message ? ", message: " : ""),
        (have_message ? error_message : ""));
#else
    error_code = errno;
    LOG_ERROR("Error on socket '%s': errno==%d, message: %s.", socket_desc, error_code, strerror(error_code));
#endif
}